Urban forest management practices generate substantial amounts of twig biomass that is commonly treated as waste, despite its potential as a source of bioactive compounds. Biological and chemical properties of methanolic extracts of 19 urban forest tree and shrub species were assessed using a multidisciplinary approach combining high-performance thin-layer chromatography (HPTLC) and HPTLC-DPPH bioautography with spectrophotometric determination of radical scavenging activity (RSA), total phenolic content (TPC), inhibition assays of skin aging-related enzymes (tyrosinase and elastase), and testing against skin pathogens Staphylococcus aureus and Pseudomonas aeruginosa. The results revealed marked differences in biological activity among extracts, driven primarily by specific phytochemical profiles. Torminalis glaberrima (Gand.) Sennikov & Kurtto (108.8 ± 6.6 μmol TE/mL) and Paliurus spina-christi Mill. (106.6 ± 1.6 μmol TE/mL) exhibited the highest RSA, correlating with elevated TPC. Acer campestre L. (51.6 ± 9.1%) showed the strongest elastase inhibition. The most pronounced tyrosinase inhibition was observed for Torminalis glaberrima (39.0 ± 3.5%), indicating a significant contribution of TPC. In contrast, the strongest antibacterial activity was recorded for Acer platanoides L. and Carpinus betulus L., despite their lower TPC values, suggesting the contribution of non-phenolics. Phenolic zones (RF 0.10, 0.28, 0.57, 0.58) were identified as putative markers of the observed bioactivities. Overall, twigs emerge as an underexplored source with considerable potential for natural cosmetics development, warranting further investigations.
Ivković et al. (Fri,) studied this question.